Stop pin carriage



` June 2, 197'()` Filed March 26, 1969 R. E. BUSCH STOP PIN CARRIAGE 2 Sheets-Sheet '1 INVENTOR. R/CHA RD E. BUSCH A TTOR/VEY.

June 2, 1970 R. E. BuscH 3.515857 STOP PIN CARRIAGE l Filed March 26, 1969 2 Sheets-Sheet 2 INVENTOR.

R/CHARD E. BUSCH A T TORNE Y.

AStates Patent O us.. 1 claim ABSTRACT on THE DISCLOSURE A pin box of solid construction having rows and columns of openings therein, stop pins slideable in said openings, eachy'stop pin being closely tted in its opening at its lowerend and rockable at its" upper end. A spring detent -nger integral with each stop pin normally holds the same against one side of its opening and also detents the pin in upper and lower positions. Upper and lower limit stops are formed on each pin,v the upper limit stop being located on the side of the pin opposite the spring detent whereby the pin can be rocked to permit such stop to pass through the opening.

This invention relates to pin carriages used in ten key calculating machines such as adding machines or the like in which the pin carriage contains a field of settable stop pins which are set by depression of different amount keys and are located to arrest differential actuators in diierent numerically arranged positions corresponding to the values of the keys depressed.

A principal object of the present invention is to provide a stop pin carriage having a minimum number of parts.

Another object is to provide a stop pin carriage having a minimum number of parts in which the pins are detinitely detented in operative and inoperative positions.

A further object is to provide a stop pin carriage which is inexpensive to manufacture and assemble.

The manner in which the above and other objects of the invention are accomplished will be readily understood on reference to the following specification when read in conjunction with the following drawings, wherein:

FIG. 1 is a sectional view through a portion of an adding machine embodying a preferred form of the present invention.

FIG. Zis an enlarged sectional view through part of the pin carriage illustrating astop pin in inoperative position and is taken substantially along the line 2 2 of FIG. 1.

FIG. 3 is a sectional view taken along line 3--3 of FIG. 2.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2.

Referring in particular to FIG. 1, the adding machine to which the present invention may be applied includes a pin carriage generally indicated at 11 which is movable along a pair of spaced support bars 12 and 13 under the urge of a suitable tension spring, not shown. An escapement mechanism of conventional type, shown partly at 14, controls movement of the carriage in a step-by-step motion under the inuence of the carriage shifting spring.

A plurality of differential actuators, one of which is shown at 15, are located directly under the pin carriage and each is arranged to be pivotally connected to a print sector of the type shown at 14 in the U.S. patent to R. E. Busch, No. 3,113,719, issued on Dec. 10, 1963. Reference may be had to such patent for an understanding of details of the well-known commercially available Addmaster Adding Machine to which the present invention may be applied.

ICC

The pin carriage comprises a pin box 16 formed of molded plastic in which are formed a plurality of rows and coordinate columns of vertically disposed openings 17. Such openings are rectangular in cross section and lips 18 are formed integral with the upper portion of the pin box to extend a short distance into the openings from one side of each thereof.

Stop pins 20 are slideably mounted in the openings 17 and each is rectangular in cross section but generally thinner than its corresponding opening, as viewed in FIG. 3. Two spaced ledges 21 are formed integrally with each pin adjacent the lower end thereof, causing the pin to fit the opening relatively closely adjacent its lower end while permitting a certain amount 'of rocking of the pin adjacent its upper end.

A central vertically arranged opening 22 is formed in each pin. A yieldable detenting finger 23 extends over the opening 22 and is formed integral with the pin adjacent its lower end whereby it may ilex into the opening 22. When the pin is in its upper position, shown in full lines in FIGS. 2 to 4, the lower sloping surface 24 of a detent head 25 formed on the upper end of the detenting finger engages the upper edge 19 of the lip 18 thus detenting the pin in its upper position against vibration, jarring, etc. In such position, a lower limit stop 26 formed integral with the pin engages the under surface of the pin box 16 to limit upward movement of the stop pin beyond its illustrated position.

A second inclined surface 27 is formed on the detent head 25 and when the pin 20 is depressed into its lower position shown by the dot-and-dash lines 20a (FIG. 4), such surface engages the under edge of the lip 18 and thus prevents possible upward movement of the pin under the influence of vibration, etc. In such position, a second limit stop 28 formed integral with the stop pin engages the upper surface of the pin box 16 to prevent downward movement of the pin beyond its position 20a.

As seen in FIG. 1, when the pins 20 are in their upper inoperative positions, they are ineffective to arrest the actuators 15 during their rightward movement but when one such pin is depressed, as at 20a, it forms a solid block against which the actuator 15 strikes. It will be noted that the upper end of each limit stop 28 is inclined as at 29. Also, the upper ends of the ledges 21 are inclined as at 30. Thus, the pins 20 may be easily and readily inserted in the openings 17 by merely pressing them upwardly through such openings, causing the dentent fingers 23 to yield inwardly into the openings 22. Thus, the pins may rock to permit the stops 28 to pass through the openings. Thereafter, the detent fingers 23 snap the pins into their normal positions shown in FIGS. 2 and 3.

If it should be desirable to remove a stop pin 20 from its inserted position, the upper end of the pin need be merely rocked to the right in FIGS. 3 or 4 against the action of the detent finger until the stop 28 is aligned with the opening 17 and then the pin is pressed downward out of the opening.

Although the pin box 16 is shown as being rectilinear in shape, it may also be curved as shown in the aforementioned Pat. 3,113,719.

I claim:

1. A stop pin carriage for a calculating machine or the like comprising a pin box having a plurality of rows and columns of stop pin openings therethrough,

stop pins slideable in said openings yfrom upper positions to lower positions,

each said stop pin closely fitting its respective said opening adjacent the lower end of said pin and being rockable in said opening adjacent its upper end, each of said stop pins having a transverse opening therethrough and terminating adjacent the opposite ends of said pin,

a yieldable detent finger integral with each said stop pin adjacent the lower end of said pin,

said detent finger extending into said transverse opening and having a detent head engageable with one side of said respective stop pin opening adjacent the upper end of s'aid transverse opening whereby to yieldably maintain said pin against the opposite side of said stop pin opening and to yieldably maintain said pin in either said upper or lower position, and

upper and lower limit stops on each said pin engageable with said pin Ibox for limiting movement of said stop pin into said upper and lower positions thereof,

each said pin being rockable in said respective stop pin opening suiciently to permit said upper limit stop to pass through said last mentioned opening.

References Cited UNITED STATES PATENTS STEPHEN I. TOMSKY, Primary Examiner 

